This invention relates to oxide-ceramic targets useful in magnetically enhanced cathode sputtering and which are based on hot-pressed indium oxide/tin oxide mixtures.
Targets of this type are known per se, and it is also known to use such targets for producing transparent electrically conductive layers.
Since the metal oxides which are press-molded into targets under pressure and at elevated temperatures are non-conductors, it is customary to sputter these targets by means of high frequency, with which even non-conductors can be sputtered without difficulty. However, high-frequency sputtering is not very suitable for large-scale industrial application, where direct-voltage sputtering is inherently preferable, but primarily requires metallic targets and not oxide-ceramic targets.
However, if metallic targets are used, the preparation of transparent oxide layers requires an oxidation to take place as the target material is applied to the surface to be coated or afterwards. This working method generally does not lead to satisfactory layers and is not even possible on all materials to be coated.